High mobility III–V-on-insulator MOSFETs on Si with ALD-Al2O3 BOX layers

We have successfully demonstrated III–V-semiconductor-on-insulator (III–V-OI) MOSFETs with ALD-Al
2
O
3
buried oxide (BOX) layers under front-gate operation, for the first time. The high electron mobilities of ∼3000 and ∼2000 cm
²
/Vs were achieved for i-InGaAs and p-InGaAs channels, respectively, formed on Al
2
O
3
/Si. Also, we have found that the InGaAs-OI channel bottom condition (the InGaAs-OI/BOX interface) is quite important for the device performance through improvements by adapting ALD-Al
2
O
3
and S passivation, resulting in high electron mobility of ∼4000 cm
²
/Vs under back-gate operation.